The printing of images for durable applications began when simple exterior signs were being reproduced in multiples. Signage has moved into all areas of graphics where images are displayed outdoors and are expected to weather the elements for years. These images have traditionally been produced with the screen-printing process and are now being produced by the ink jet process. These two printing processes are capable of printing on durable substrates, in large formats, and with a heavy ink deposit that will endure the elements.
There are established ASTM methods for the weathering of paints, inks, coatings, and substrates to predict the exterior durability of a construction. The weathering prediction processes are all based on how solid single-color inks or coatings will fade. Images printed by ink jet are all produced with the four subtractive CMYK inks in a range of tonal percentages.
This paper outlines the process and the reasoning to create accurate weathering predictions for four color process printed images. This process will generate accurate aging profiles that can be applied to any image that may be used in exterior applications. The resulting color profiles can be applied to images on monitors, proofs, and full-size prints.